Definitions

• (Nonpathological) dissociation: a psychological defense mechanism (natural protective response) to a traumatic or very stressful experience.
  • Disruption of normal integration of memories, identity, perception, experiences, and emotions to cope with stress or stimulation overload
  • Detachment from self (physical and emotional experiences) and/or surroundings
  • Can be a fleeting phenomenon (e.g. daydreaming) or more severe with impaired consciousness
• Pathological dissociation: an excessive reaction to a traumatic or very stressful experience that is characterized by:
  • Positive symptoms: derealization (the mind detaches from one’s environment), fragmentation of identity, and depersonalization (the mind detaches from one’s self)
  • Negative symptoms: amnesia, altered consciousness (e.g., narrowed awareness, trance), altered behavior

Dissociative amnesia

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• Diagnostic criteria
  1. Inability to recall autobiographical information after a traumatic or stressful event
  2. Symptoms cause significant social or occupational impairment.
  3. Symptoms are not due to substance use or another medical condition.
  4. Symptoms cannot be explained by another psychiatric disorder (e.g., dissociative identity disorder, acute stress disorder, posttraumatic stress disorder).
  5. May present with dissociative fugue: wandering or purposeful travel (associated with amnesia of identity or autobiographical information)